Finger-mountable ablation device

ABSTRACT

A surgical device is disclosed, and includes a pair of finger-mountable annular members, each having an electrode disposed thereon. An optical member is disposed on at least one of the pair of finger-mountable annular members and has a first set of light transmitting properties corresponding to a first set of physical parameters of at least one of the finger-mountable annular members. At least one finger-mountable annular member is configured to transition to a second set of physical parameters being different from the first set of physical parameters. The optical member is configured to transition from a first set of light transmitting properties to a second set of light transmitting properties, the second set of light transmitting properties corresponding to the second set of physical parameters, the second set of light transmitting properties being different from the first set of light transmitting properties.

CROSS REFERENCE TO RELATED APPLICATION

The present application is a continuation application of U.S. patentapplication Ser. No. 14/887,480, filed Oct. 20, 2015, which is acontinuation application of U.S. patent application Ser. No. 13/803,762,filed Mar. 14, 2013, now U.S. Pat. No. 9,161,812, which claims thebenefit of and priority to U.S. Provisional Application No. 61/673,651,filed on Jul. 19, 2012, the entire contents of all of which areincorporated herein by reference.

BACKGROUND

1. Technical Field

The present disclosure relates generally to an electrosurgical device,and more particularly to one or more finger-mountable annular membersincluding an electrode for treating tissue and an optical fiber for thedetection of the changing physical characteristics of thefinger-mountable annular member.

2. Background of Related Art

Electrosurgical instruments are commonly used in open and minimallyinvasive surgical procedures. Because nerve and muscle stimulation ceaseat 100,000 cycles per second (100 kHz), electrosurgical procedures canbe performed safely at radio frequencies (“RF”) above 100 kHz. At thesefrequencies, electrosurgical energy can pass through a patient withminimal neuromuscular stimulation.

Electrosurgery involves application of high RF electrical current to asurgical site to cut, ablate, or coagulate tissue. In monopolarelectrosurgery, a source or active electrode delivers RF energy from theelectrosurgical generator to the tissue and a return electrode carriesthe current back to the generator. The source electrode is typicallypart of the surgical instrument held by the surgeon and applied to thetissue to be treated. A patient return electrode is placed remotely fromthe active electrode to carry the current back to the generator.

In bipolar electrosurgery, one of the electrodes of the hand-heldinstrument functions as the active electrode and the other as the returnelectrode. The return electrode is placed in close proximity to theactive electrode such that an electrical circuit is formed between thetwo electrodes, e.g., electrosurgical forceps, graspers, pencils, andthe like. In this manner, the applied electrical current is limited tothe body tissue positioned between the electrodes. When the electrodesare sufficiently separated from one another, the electrical circuit isopen and thus incidental contact of body tissue with either of theseparated electrodes inhibits current flow.

Bipolar electrosurgical instruments often include opposed electrodesdisposed on opposing tissue engaging faces of a pair of cooperatingmembers such as jaws, graspers, or plates. The electrodes are charged toopposite electrical potentials such that an electrosurgical current maybe selectively transferred through tissue grasped between theelectrodes. However, electrosurgical instruments often have a limitedrange of motion, e.g., due to mechanical design constraints. Thislimited range of motion may be disadvantageous to a surgeon working inan area that requires a complex series of movements. In such situations,it may be desirable to use electrosurgical instruments that facilitate awide and variable range of motion to allow for complex surgicalarticulation. Thus, the mechanical nature of some electrosurgicalinstruments may limit the amount of tactile sensory feedback received bythe surgeon during a procedure. In certain procedures, it may be usefulto have the ability to determine how much pressure to apply to acoagulation, cutting, or sealing surface.

SUMMARY

It would be desirable to provide a more dexterous electrosurgicalinstrument for facilitating complex motions during an endoscopic orendoluminal procedure. It would further be desirable to provide such aninstrument having the capability to provide feedback to an operator onthe performance and the condition of the electrosurgical device andsurrounding tissue, e.g., temperature, mechanical strain, and otherrelevant characteristics.

The present disclosure relates to an electrosurgical apparatus andmethods for performing electrosurgical procedures. More particularly,the present disclosure relates to electrosurgically coagulating andsealing tissue. As is traditional, the term “distal” refers herein to anend of a device that is farther from an operator, and the term“proximal” refers herein to the end of a device which is closer to theoperator. In further aspects of the present disclosure, “distal” mayrefer to an end or portion of a device closest to an operator'sfingertip, and “proximal” may refer to an end or portion of a devicefurthest from an operator's fingertip.

As used herein, “bipolar” electrosurgery involves one of a pair ofelectrodes functioning as an active electrode and the other electrodefunctioning as a return electrode. The return electrode is placed inclose proximity to the active electrode such that an electrical circuitis formed between the two electrodes.

Further, “monopolar” electrosurgery involves the use of a source oractive electrode to deliver RF energy from an electrosurgical generatorto tissue and a return electrode carries the current back to theelectrosurgical generator. A patient return electrode is placed remotelyfrom the active electrode to carry the current back to the generator.

As described herein, electrosurgical tissue sealing may includeelectrosurgical fulguration. Electrosurgical fulgration comprises theapplication of an electric spark to biological tissue, for example,human flesh or the tissue of internal organs, without significantcutting. The spark is produced by bursts of RF electrical energygenerated from an appropriate electrosurgical generator. Generally,fulguration is used to dehydrate, shrink, necrose, or char the tissue.As a result, the instrument is primarily used to stop bleeding andoozing. These operations are generically embraced by the term“coagulation”. Meanwhile, electrosurgical cutting includes the use ofthe applied electric spark to tissue which produces a cutting effect.Electrosurgical sealing includes utilizing both electrosurgical energyand pressure to melt the tissue collagen into a fused mass.

According to one aspect of the present disclosure, a surgical deviceincludes a pair of finger-mountable annular members, each having anelectrode disposed thereon. An optical member is disposed on at leastone of the finger-mountable annular members and has a first set of lighttransmitting properties corresponding to a first set of physicalparameters of at least one of the finger-mountable annular members. Atleast one finger-mountable annular member is configured to transition toa second set of physical parameters, the second set of physicalparameters being different from the first set of physical parameters.The optical member is configured to transition from a first set of lighttransmitting properties to a second set of light transmittingproperties, the second set of light transmitting propertiescorresponding to the second set of physical parameters being differentfrom the first set of light transmitting properties.

In a further aspect of the present disclosure, the first and second setsof physical parameters are selected from the group consisting oftemperature and mechanical strain. The first and second sets of lighttransmitting properties may include transmittance.

According to another aspect of the present disclosure, a surgical deviceincludes a first finger-mountable annular member and a secondfinger-mountable annular member, each of the first and secondfinger-mountable annular members including a tissue engaging surface,the tissue engaging surfaces of the respective first and secondfinger-mountable annular members spaced away from each other in opposedrelation. An electrode is disposed on each of the respective tissueengaging surfaces, and each electrode is configured to be coupled to anelectrosurgical generator. A sensor assembly is operably coupled to atleast one of the first finger-mountable annular member and the secondfinger-mountable annular member, and includes an optical member and alight source, the optical member configured to transmit light from thelight source. A change in the transmission of light through the opticalmember corresponds to a changed condition of at least one of the firstand second finger-mountable annular members.

In another aspect of the present disclosure, each of the first andsecond finger-mountable annular members defines an opening therethrough.The opening of each of the first and second finger-mountable annularmembers may be configured to engage a mountable member.

In a further aspect of the present disclosure, the changed condition ofat least one of the first and second finger-mountable annular membersincludes at least one of a change in temperature and a change inmechanical strain.

In yet a further aspect of the present disclosure the optical member isassociated with the first finger-mountable annular member, and a secondoptical member is associated with the second finger-mountable annularmember. The optical member is at least partially disposed within aportion of one of the first and second finger-mountable annular members.

In another aspect of the present disclosure, the optical member mayinclude a fiber Bragg grating. The fiber Bragg grating may reflect afirst wavelength of light transmitted from the light source. In thechanged condition, the fiber Bragg grating may reflect a secondwavelength of light from the light source, the second wavelength oflight being different from the first wavelength of light. The fiberBragg grating may include a plurality of segments disposed in a periodicpattern, and each of the plurality of segments has a predeterminedrefractive index.

In a further aspect of the present disclosure, the optical memberdefines a length and has a refractive index that varies along the lengthof the optical member.

In yet another aspect of the present disclosure, each of the electrodesis configured to pass a current therebetween.

A further aspect of the present disclosure describes a method ofmeasuring strain through an electrosurgical device, and includesproviding an electrosurgical device having a pair of electrodessupported on a respective pair of finger-mountable annular members, atleast one of the finger-mountable annular members including a lighttransmissive member, the light transmissive member including a spacedplurality of segments configured to reflect at least one wavelength oflight and transmit at least one wavelength of light. The method furtherincludes projecting light through the light transmissive member andmeasuring a first wavelength of light transmitted through the lighttransmissive member. The method additionally includes forcing the pairof finger-mountable annular members into contact such that a force isexerted on the light transmissive member, the force causing a change inspacing between the plurality of segments, and measuring a secondwavelength of light transmitted through the light transmissive memberafter the force is applied. The method also includes comparing the firstwavelength of light to the second wavelength of light to determine achange in spacing between the plurality of segments resulting from theforce.

In a further aspect of the present disclosure, the step of comparing thefirst wavelength of light to the second wavelength of light includesdetermining the amount of strain experienced by one of thefinger-mountable annular members including the light transmissivemember.

In another aspect of the present disclosure, the step of providing anelectro surgical device includes supplying a current between the pair ofelectrodes. In a further aspect of the present disclosure, the methodfurther includes the step of engaging a section of tissue such that thesection of tissue is disposed between the pair of finger-mountableannular members.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the presentdisclosure and, together with the detailed description of theembodiments given below, serve to explain the principles of thedisclosure.

FIG. 1 is a perspective view of an embodiment of an electrosurgicaldevice according to the present disclosure;

FIG. 2 is a perspective view of an optical fiber according to thepresent disclosure;

FIG. 3 is a perspective view of a connector according to an embodimentof the present disclosure;

FIG. 4 is an exploded, perspective view of the connector of FIG. 4according to an embodiment of the present disclosure;

FIG. 5 is a side, cross sectional view of a pair of the finger-mountableannular members of FIG. 1 in a spaced-apart configuration according tothe present disclosure.

FIG. 6 is a side, cross sectional view of a pair of the finger-mountableannular members of FIG. 1 in an approximated configuration according tothe present disclosure; and

FIG. 7 is a front view of the display system of FIG. 1 according to thepresent disclosure.

DETAILED DESCRIPTION

The present disclosure provides for a system and method for providing avariety of sensor feedback regarding operation of an electrosurgicaldevice including a pair of finger-mountable annular members including,but not limited to, temperature of the finger-mountable annular membersand the surrounding tissue, pressure exerted on the finger-mountableannular members, position and pressure of various mechanical componentsof the electrosurgical device, and identification informationcorresponding to the electrosurgical device. Although the feedbacksystem according to present disclosure is described below with respectto a pair of finger-mountable annular members, the system may beutilized in a variety of surgical instruments, including but not limitedto, open surgical forceps, tweezer-type devices, graspers, staplers,pencils, needles, and the like. Although this configuration is typicallyassociated with instruments for use in laparoscopic or endoscopicsurgical procedures, various aspects of the present disclosure may bepracticed with traditional open instruments and in connection withendoluminal procedures as well.

With reference to FIG. 1, an embodiment of an electrosurgical device 10is shown, and includes a pair of finger-mountable annular members 12 a,12 b that are electrically coupled with a source of electrosurgicalenergy such as electrosurgical generator 40. The generator 40 may be anysuitable generator such as the LIGASURE® Vessel Sealing Generator andthe FORCETRIAD® Generator sold by Surgical Solutions of Boulder, Colo.Other suitable electrosurgical generators as are known in the art may beused with electrosurgical device 10. The generator 40 includes a displaysystem 60, which may be integrally formed with the generator 40, e.g.,disposed in the same housing, and will be described in further detailbelow.

A cable 42 extends between each finger-mountable annular member 12 andthe generator 40. Accordingly, cable 42 may be split between eachfinger-mountable annular member 12 a, 12 b and joined approachinggenerator 40. A connector 43 is disposed on an end of the cable 42 andinterfaces with generator 40 such that the finger-mountable annularmembers 12 a, 12 b may be selectively coupled and decoupled electricallyfrom the generator 40. In some embodiments, the cable 42 includesadditional connectors 43 such that finger-mountable annular members 12a, 12 b may be selectively coupled or decoupled to the cable 42 in thismanner.

As shown, each finger-mountable annular member 12 a, 12 b includes amounting portion 16 a, 16 b and a tissue engaging portion 20 a, 20 b,respectively. The finger-mountable annular members 12 a, 12 b, as shown,may be spaced apart in opposed relation on an operator's index fingerand thumb. In some embodiments, finger-mountable annular members 12 a,12 b may be engaged by other combinations of an operator's digits, ormay be configured to engage a driving mechanism, such as a robotic armor mechanical actuator.

Mounting portions 16 a, 16 b as shown are configured as substantiallyC-shaped or open cylindrical members. A respective pair of arcuatemembers 18 a ₁, 18 b ₁ and 18 a ₂, 18 b ₂, extend from a proximalportion of the tissue engaging portions 20 a, 20 b, defining openings 19a ₁, 19 b ₁. Arcuate members 18 a ₁, 18 b ₁ and 18 a ₂, 18 b ₂ arecurved in a manner so as to approach a respective circumferential gap 19b ₁, 19 b ₂. The openings 19 a ₁, 19 a ₂ and the gaps 19 b ₁, 19 b ₂permit the insertion of a mountable member, such as a portion of anoperator's finger, as shown. Accordingly, arcuate members 18 a ₁, 18 b ₁and 18 a ₂, 18 b ₂ may be resilient or flexible and configured toradially flex in tension to widen gaps 19 b ₁, 19 b ₂ for the receptionof a respective mountable member. Suitable materials for arcuate members18 a ₁, 18 b ₁ and 18 a ₂, 18 b ₂ may include, but are not limited to,metal, polymeric materials, and composites. In some embodiments,openings 19 a ₁, 19 a ₂ may be shaped, dimensioned, or otherwiseconfigured to receive any number of operator's digits or a drivingmechanism, as described above. In further embodiments, mounting portions16 a, 16 b may be any suitable shape, such as a loop or ringconfiguration, a conical sleeve with a closed distal end, or an opencircular frame configured and dimensioned to fit around a finger. Thoseskilled in the art of the present disclosure will envision othersuitable configurations and arrangements for mounting portions 16 a, 16b.

Tissue engaging portions 20 a, 20 b are exposed on a distally-facingsurface of the respective mounting portions 16 a, 16 b. A tissueengaging surface 22 a, 22 b is defined on each respective tissueengaging portion 20 a, 20 b and may have surface features for engagementwith a section of tissue “T” (FIG. 5), such as knurls, grooves, spikes,or the like. In some embodiments, the finger-mountable annular members12 a, 12 b are oriented such that the respective tissue engagingsurfaces 22 a, 22 b are exposed facing away from an operator's fingerpad. In some embodiments, tissue engaging surfaces 22 a, 22 b may havean arcuate or otherwise contoured profile for engagement withlike-shaped tissue sections. The tissue engaging portions 20 a, 20 b maybe attached to or integrally formed with the mounting portions 16 a, 16b. In further embodiments, tissue engaging portions 20 a, 20 b may besnap-fit, adhered, secured with sutures or another binding member, orultrasonically welded to mounting portions 16 a, 16 b. One skilled inthe art of the present disclosure will envision other suitable couplingbetween mounting portion 16 a, 16 b and tissue engaging portions 20 a,20 b.

One or more electrodes 30 a (FIG. 5), 30 b are disposed on eachrespective tissue engaging surface 22 a, 22 b of the finger-mountableannular members 12 a, 12 b. Electrodes 30 a, 30 b may be attached torespective tissue engaging surfaces 22 a, 22 b, or may be partiallyrecessed within and protrude from the tissue engaging surfaces 22 a, 22b. In some embodiments, each entire tissue engaging surface 22 a, 22 bmay be configured as an electrode. The electrodes 30 a, 30 b may befabricated from any electrically-conductive material or may be coatedwith an electrically conductive material, e.g., stainless steel,aluminum, platinum, titanium, copper, gold or silver. Electrodes 30 a,30 b may be connected to the generator 40 through cable 42, or may bedirectly connected to the generator 40 through separate transmissionlines (not shown). In some embodiments, transmission lines or a portionof cable 42 may be integrally formed with or disposed within a channeldefined in the finger-mountable annular members 12 a, 12 b, as will bedescribed in further detail below.

One or more fibers 500 a ₁, 500 b ₁ and 500 a ₂, 500 b ₂ (FIGS. 5-6) areassociated with electrosurgical device 10. Fibers 500 a ₁, 500 b ₁ and500 a ₂, 500 b ₂ may be optical sense fibers, such as phosphate glassfibers, or may be any suitable type of light transmissive member. Fibers500 a ₁, 500 b ₁ and 500 a ₂, 500 b ₂ may be disposed on, within orattached to one or both finger-mountable annular members 12 a, 12 b, aswill be described further below.

Fibers 500 a ₁, 500 b ₁ and 500 a ₂, 500 b ₂ are configured to sense oneor more sets of physical parameters, e.g., temperature and mechanicalstrain, within the finger-mountable annular members 12 a, 12 b and othercomponents of the electrosurgical device 10 and may provideidentification information of the finger-mountable annular members 12 a,12 b to the generator 40. In this manner, fibers 500 a ₁, 500 b ₁ and500 a ₂, 500 b ₂ act as a sensor assembly, and may be coupled with alight source. The generator 40 also includes an interrogator 41 a(FIG. 1) coupled to the fibers 500 a ₁, 500 b ₁ and 500 a ₂, 500 b ₂that decodes the optically encoded strain information from fibers 500 a₁, 500 b ₁ and 500 a ₂, 500 b ₂ into electrical signals compatible withthe computer control hardware of the generator 40. The generator 40includes a controller 41 b, which is used to calculate temperature andforces exerted on the fibers 500 a ₁, 500 b ₁ and 500 a ₂, 500 b ₂, asdescribed in further detail below. The controller 41 b may be anysuitable type of logic circuit, such as field programmable gate array,processor, and the like. The generator 40 also includes a receptacle 45(FIG. 1) configured to interface with the connector 43.

With reference now to FIG. 2, the fibers 500 a ₁, 500 b ₁ and 500 a ₂,500 b ₂ and fiber 400 are described with respect to a fiber 300 to avoidrepetition. The fiber 300 includes a core 302, a cladding 304 disposedover the core 302, and a buffer coating 306 covering the cladding 304.The fiber 300 also includes one or more fiber Bragg gratings (FBG) 308.Multiple gratings 308 may be written, e.g., etched, into the fiber 300if the gratings 308 are formed in such a way as to use differentwavelengths. This is particularly useful for using a single fiber tosense multiple locations within the instrument. In further embodiments,multiple fibers 300 may be included each having one or more gratings308.

The gratings 308 include a plurality of reflection points 307 writteninto the fiber 300 at periodic spacing “A.” In some embodiments, thegrating 308 may be written into the fiber 300 using high intensitypulses from a laser (e.g., argon fluoride excimer laser with a phasemask). As the fiber 300 undergoes mechanical strain (e.g., a change inlength) due to temperature and pressure changes, the spacing A ismodified due to stretching or contraction of the fiber 300. The effectsof strain and temperature are quantified by measuring the wavelengthshift in light reflected by the reflection points 307 based on theformula (I), which is reproduced below:

$\begin{matrix}{\frac{\Delta \; \lambda}{\lambda_{0}} = {{k*ɛ} + {\alpha_{\delta}*\Delta \; T}}} & (I)\end{matrix}$

In formula (I), Δλ is the wavelength shift, λ₀ is the base wavelength, kis a gage factor, which is a difference between 1 and a photo-elasticcoefficient, ρ, ε is strain, ΔT is a temperature change, and α_(δ) is achange of the refraction index.

In this manner, the light transmissive properties, namely transmittance,of the fiber 300 corresponds to a set of physical parameters of thefinger-mountable annular members 12 a, 12 b (FIG. 1). The lighttransmissive properties of the fiber 300 may transition with changingphysical parameters of the finger-mountable annular members 12 a, 12 b.

With additional reference to FIGS. 3 and 4, an embodiment of connector43 is shown coupled to cable 42 and includes a housing portion 106having a first-half section 106 a and a second half-section 106 boperatively engagable with one another. Half-sections 106 a, 106 b areconfigured to retain an active pin 112 a, a return pin 112 b, an opticalcoupler 108, and a plurality of electrical contacts 110 disposed on aprong 114. The pin 112 a is coupled to the wire 46 a and the pin 112 bis coupled to the wire 46 b. The electrical contacts 110 are coupled tocontrol leads 111, which may be coupled to various electrical controls,e.g., switch 36. The optical coupler 108 is connected to a fiber 400 ata proximal end 401 of the fiber 400. Fiber 400 is substantially similarto fiber 300 discussed above. The receptacle 45 includes correspondingconnectors for coupling the pins 112 a, 112 b, contacts 110, and opticalcoupler 108 to the generator 40, namely, energy-generating components(e.g., RF output stage), sensor circuits, the interrogator 41 a, and thecontroller 41 b.

The connector 43 includes an identification assembly 200 including thefiber 400, which includes a fiber Bragg grating 408 at a proximal end401 thereof. The proximal end 401 of the optical fiber 400 that includesthe fiber Bragg grating 408 is mounted loosely within the housing 106 ofthe connector 43 such that strain does not transfer to the fiber 400. Insome embodiments, the fiber 400 may be thermally insulated (e.g.,potting of the housing 106) to prevent thermal effects of the fiberBragg grating 408. This configuration allows the fiber Bragg grating 408to be unaffected by thermal and strain imposed on the connector 43.Accordingly, the fiber Bragg grating 408 provides the same feedback wheninterrogated by the interrogator 41 a. The fiber Bragg grating 408 maybe individually tailored to encode identification informationcorresponding to a specific device (e.g., finger-mountable annularmembers 12 a, 12 b). The identification information that may be encodedin the fiber Bragg grating 408 may include, but is not limited to,serial number, model number, usage settings, configuration settings, andthe like. Different identification information may be encoded by varyingthe number, thickness and periodic spacing between reflection points ofthe fiber Bragg grating 408. The interrogator 41 a may interrogate theidentification assembly 200 upon insertion of the connector 43 into thereceptacle 45. Interrogation may be triggered by detection of theinsertion using one or more proximity switches, limit switches, radiofrequency tags, and the like.

Referring now to FIGS. 5 and 6, the finger-mountable annular members 12a, 12 b may be moved between an open position and spaced apart position(FIG. 5), wherein tissue “T” is received between the finger-mountableannular members 12 a, 12 b, and a closed or clamped configuration (FIG.6), wherein the tissue T is clamped and sealed. As described above,finger-mountable annular members 12 a, 12 b may be engaged with anoperator's fingers and subject to a “pinching” movement to effectapproximation. As the electrodes 30 a, 30 b are electrically coupled tocable 42 (FIG. 1), and thus to the generator 40 (FIG. 1), RF energy maybe transmitted between electrodes 30 a, 30 b, as shown. In someembodiments, the opposed tissue engaging surfaces 22 a, 22 b with therespective electrodes 30 a, 30 b disposed thereon are electricallycoupled to opposite terminals, e.g., active and return terminals,associated with the generator 40. Thus, bipolar energy may be providedthrough the tissue engaging surfaces 22 a, 22 b. Alternatively, thetissue engaging surfaces 22 a, 22 b may be configured for deliveringmonopolar energy to the tissue “T”. In a monopolar configuration, one orboth tissue engaging surfaces 22 a, 22 b deliver electrosurgical energyfrom an active terminal coupled to one or more of the electrodes 30 a,30 b, while a return pad (not shown) is placed generally beneath apatient and provides a return path to the opposite terminal, of thegenerator 40

As finger-mountable annular members 12 a, 12 b are approximated to theclosed configuration of FIG. 6, the tissue engaging surfaces 22 a, 22 bmay be configured to provide a consistent pressure to tissue T graspedtherebetween. To provide a consistent and effective tissue seal, thepressure may be from about 3 kg/cm² to about 16 kg/cm² and, in someembodiments, from about 7 kg/cm² to about 13 kg/cm². As described infurther detail below, the pressure being measured by fiber 500 a ₁and/or 500 a ₂ is displayed on display 60, allowing the operator tocontrol the grasping pressure. Additionally, an appropriate distancebetween tissue engaging surfaces 22 a, 22 b, e.g., from about 0.001inches to about 0.006 inches should be maintained and, in someembodiments, from about 0.002 inches to about 0.005 inches. In furtherembodiments, a minimum desired separation or gap distance is maintainedbetween the tissue engaging surfaces 22 a, 22 b by a stop 24 a, 24 b orother protrusion formed on one or more of the tissue engaging portions20 a, 20 b of finger-mountable annular members 12.

As described above, the opposing finger-mountable annular members 12 a,12 b include the respective fibers 500 a ₁, 500 b ₁ and 500 a ₂, 500 b₂. For purposes of simplicity and consistency, use of fibers 500 a ₁,500 b ₁ and 500 a ₂, 500 b ₂ to monitor temperature and pressure aredescribed hereinbelow with reference to finger-mountable annular member12 a only. Accordingly, references to channels 28 b, 29 b housing theproximal and distal ends 501 a ₂, 501 b ₂ and Fiber Bragg gratings 508 a₂, 508 b ₂ of the respective fibers 500 a ₂, 500 b ₂ of annular member12 b will not be described. In some embodiments, fibers 500 a ₁, 500 b ₁and 500 a ₂, 500 b ₂ may be disposed within one or more finger-mountableannular members 12 a, 12 b.

The first fiber 500 a ₁ is disposed in a first channel 28 a definedthrough the tissue engaging portion 20 a near tissue engaging surface 22a. The second fiber 500 b ₁ is disposed in a second channel 29 a spacedaway from the first channel 28 a. The second channel 29 a may bedisposed within a portion of the arcuate members 18 a ₁, 18 b ₁ (FIG. 1)or may be disposed within another portion of the finger-mountableannular member 12 a spaced away from the channel 29 a. In someembodiments, the finger-mountable annular members 12 a may be formed ormolded about the fibers 500 a ₁, 500 b ₁.

The fibers 500 a ₁, 500 b ₁ include distal ends 501 a ₁, 501 b ₁,respectively, which are disposed within the first and second channels 28a, 29 a of the finger-mountable annular member 12 a. Each of the fibers500 a ₁, 500 b ₁ includes one or more fiber Bragg gratings 508 a ₁, 508b ₁ disposed within first and second channels 28 a, 29 a, respectively.The first and second channels 28 a, 29 a may be filled with thermallyand electrically conductive material. The material may be a liquid, suchas saline. When light is projected through fibers 500 a ₁, 500 b ₁, bothof the fiber Bragg gratings 508 a ₁, 508 b ₁, measure temperature at ornear the finger-mountable annular members 12 a. The fiber 500 a ₁ issecuredly mounted within the finger-mountable annular member 12 a, e.g.,glued thereto along the entire length thereof, to provide strainmeasurements imposed on the finger-mountable annular member 12 a. Strainmeasurements allow for determination of pressure exerted on thefinger-mountable annular member 12 a. However, the gratings 508 a ₁ areaffected by both temperature and strain. To obtain accurate strainmeasurements at the finger-mountable annular member 12 a, fiber 500 b ₁is mounted in a less secure manner to finger-mountable annular member 12a (e.g., only at the distal end 501 b ₁) such that strain does nottransfer to the fiber 500 b ₁. This configuration allows the fiber 500 b₁ to be affected only by temperature. Thus, the fiber 500 a ₁ providessensor feedback regarding temperature and strain to the interrogator 41a while the fiber 500 b ₁ only provides temperature feedback. Thetemperature feedback from the fiber 500 b ₁ is used by the interrogator41 a and/or the controller 41 b to determine the temperature at thefinger-mountable annular member 12 a and the tissue site, as well as thestrain by correcting the feedback from the fiber 500 a ₁ using thefeedback from the fiber 500 b ₁. The feedback signal from the fiber 500b ₁ is used to remove the temperature component of the feedback signalfrom the fiber 500 a ₁ to obtain the strain component. In this manner,measuring a first wavelength of light transmitted through the fibers 500a ₁, 500 b ₁, forcing the finger-mountable annular members 12 a, 12 binto contact such that a force is exerted on the fibers 500 a ₁, 500 b ₁causing a change in spacing between the Bragg gratings 508 a ₁ 508 b ₁,and measuring a second wavelength of light transmitted through thefibers 500 a ₁, 500 b ₁ allows a comparison of the changed spacingbetween the Bragg gratings 508 a ₁, 508 b ₁ indicative of mechanicalstrain and changed temperature.

The temperature and strain feedback may be used by the controller 41 bto control the output of the generator 40. In some embodiments, theadjustments to the output of the generator 40 may include, but are notlimited to, changing modes (e.g., cutting, coagulation, sealing),changing power level (e.g., voltage and/or current), duty cycle,terminating energy, and combinations thereof. This reading may beprovided to the generator 40 which may continuously display theresulting strain readings as pressure imposed on the annular members 12a, 12 b and tissue T. In some embodiments, the generator 40 may outputan indication that a predetermined pressure has been reached. Thisindication may be used as one of the conditions in determining whether atissue seal is complete.

Additionally, during an electrosurgical procedure, the characteristicsof the tissue T may change such that the tissue T may resist movement ofthe electrode 30 a differently. For example, charred tissue will berelatively tougher and have a tendency to resist movement. In someembodiments, the three-dimensional strain in the x, y, z coordinates,i.e., the ratio of the deformation of particular points within theelectrode 30 a relative to the original positioning of those pointswithin the electrode 30 a, will provide a mechanism to monitor andregulate the effects of the electrode 30 a upon the tissue T.

Turning to FIG. 7, and as described above, and as described above,generator 40 may include a display system 60. Specifically, the displaysystem 60 may be coupled to the interrogator 41 a and/or the controller41 b (FIG. 1). Display system 60 may include a monitor or a graphictouchscreen display, as well as switches and illuminated indicators.Further, the controller 41 b may be configured to execute algorithms forconverting raw strain and temperature signals into one or more processeddata, e.g., pressure measurements. In some embodiments, the displaysystem 60 may include controls 66 allowing an operator to cycle throughmultiple display screens.

The display system 60 displays a graphical representation of theperformance of finger-mountable annular members 12 a, 12 b or anothersurgical device. This graphical representation may include an imagecorresponding to the temperature and/or strain readings captured by theinterrogator 41 a and/or controller 41 b. As shown, display system 60may display a measured temperature or applied pressure by the annularmembers 12 a, 12 b over a time interval. Such a temperature gauge 62 maybe measured over a range of, e.g., 125 to 150 degrees Celsius, and apressure gauge 64 may be measured over a range of, e.g., 3 to 16 kg/cm².In some embodiments, the display system 60 may also displayinstantaneous pressure and/or temperature values. In furtherembodiments, display system 60 may display pressure and temperature invarious real and graphical representations, such as bar graphs, whichmay be color-coded to represent the magnitude of pressure andtemperature readings (e.g., red to represent high temperature and/orpressure, yellow to represent intermediate temperature and/or pressure,and green to represent low temperature and/or pressure, and combinationsthereof). In this manner, display system 60 may provide a real-timepressure applied to tissue T by an operator as well as the thermalconditions at the tissue T. With this direct feedback, an operator,being in direct mechanical control of the electrodes 30 a, 30 b, maychoose to alter or discontinue an electrosurgical procedure accordingly.Further, an operator may use the display system 60 to choose anothersurgical instrument or a differently-sized or configuredfinger-mountable annular member 12 a, 12 b with which to perform anelectrosurgical surgical procedure.

While several embodiments of the disclosure have been shown in thedrawings, it is not intended that the disclosure be limited thereto, asit is intended that the disclosure be as broad in scope as the art willallow and that the specification be read likewise. Therefore, the abovedescription should not be construed as limiting, but merely asexemplifications of particular embodiments. Those skilled in the artwill envision other modifications within the scope and spirit of theclaims appended hereto. Although the foregoing disclosure has beendescribed in some detail by way of illustration and example, forpurposes of clarity or understanding, it will be obvious that certainchanges and modifications may be practiced within the scope of theappended claims.

1-20. (canceled)
 21. An electrosurgical system, comprising: anelectrosurgical device including at least one electrode and a lighttransmissive member; and an electrosurgical generator coupled to theelectrosurgical device, the electrosurgical generator including: a lightsource coupled to the light transmissive member and configured toproject light therethrough; an interrogator configured to measure achange in a wavelength of the light in response to a change in at leastone physical parameter of the electrosurgical device; and a controllerconfigured to calculate the change in the at least one physicalparameter based on the change in the wavelength of the light.
 22. Theelectrosurgical system according to claim 21, wherein theelectrosurgical device includes: a pair of finger-mountable annularmembers, each of the finger-mountable annular members including: aninner surface configured to be engaged with a finger; and an outersurface having an electrode disposed thereon.
 23. The electrosurgicalsystem according to claim 21, the electrosurgical generator includes adisplay configured to display the at least one physical parameter. 24.The electrosurgical system according to claim 23, wherein the at leastone physical parameter is temperature or mechanical strain.
 25. Theelectrosurgical system according to claim 21, wherein the lighttransmissive member includes a fiber Bragg grating.
 26. Theelectrosurgical system according to claim 25, wherein the fiber Bragggrating includes a plurality of segments disposed in a periodic pattern.27. The electrosurgical system according to claim 26, wherein each ofthe plurality of segments has a predetermined refractive index.
 28. Anelectrosurgical system, comprising: an electrosurgical device includingat least one electrode and a light transmissive member including aplurality of segments; and an electrosurgical generator coupled to theelectrosurgical device, the electrosurgical generator including: a lightsource coupled to the light transmissive member and configured toproject light therethrough; an interrogator configured to measure achange in a wavelength of the light reflected by the plurality ofsegments in response to a change in a spacing between the plurality ofsegments of the light transmissive member, which is indicative of achange in at least one physical parameter of the electrosurgical device;and a controller configured to calculate the change in the at least onephysical parameter based on the change in the wavelength of the light.29. The electrosurgical system according to claim 28, wherein theelectrosurgical device includes: a pair of finger-mountable annularmembers, each of the finger-mountable annular members including: aninner surface configured to be engaged with a finger; and an outersurface having an electrode disposed thereon.
 30. The electrosurgicalsystem according to claim 28, the electrosurgical generator includes adisplay configured to display the at least one physical parameter. 31.The electrosurgical system according to claim 28, wherein the at leastone physical parameter is temperature or mechanical strain.
 32. Theelectrosurgical system according to claim 28, wherein each of theplurality of segments are disposed in a periodic pattern.
 33. Theelectrosurgical system according to claim 28, wherein each of theplurality of segments has a predetermined refractive index.